module.exports = {
    //对象转成sql语句的set字符串，若有undefined项，自动丢弃
    //obj: {key:val,key:val}
    toSqlSetStr(obj) {
        return JSON.stringify(obj).replace(/[{}]/g, "").replace(/["']:/g, ":").replace(/,["']/g, ",").replace(/:/g, "=").substr(1);
    }
}